One example of this type of powder inhaler is disclosed in PTL 1. The powder inhaler is so structured that a patient may inhale the stored powder medicament through a mouthpiece. Specifically, when the patient depresses the operation button of the inhaler, a metered dose powder medicament is disposed to the inhalation position, and, in this condition, the patient can take the metered dose of powder medicament by inhaling air while holding the mouthpiece with his/her mouth.